The present invention relates to a separating device comprising two cylinders and a one piece pin stripping device. In particular, this invention relates to a device having a stripping plate with fingers adapted to extend within a groove formed in the surface of one of the separating cylinders, whereby waste material coupled to one of the cylinders by the one-piece pin during the formation of a folding carton, envelope or other pattern from a blank can be stripped from the cylinder.
In manufacturing folding cartons, envelopes or other similar items from a blank, a waste product or skeleton is typically produced. Generally, the blank is first cut into the pattern of the folding carton, envelope or other desired pattern using a die or other type of cutting device. After the pattern is cut, a skeleton remains surrounding the pattern or within the pattern if a window portion is incorporated into the folding carton. To separate the skeleton from the pattern using the devices of the prior art, both the skeleton and pattern are fed into a separating mechanism. The separating mechanism typically includes an upper and a lower cylinder, with the lower cylinder having a plurality of pins extending therefrom. As the skeleton is fed between the cylinders, the pins are arranged to penetrate and thereby couple the skeleton to the lower cylinder, while the pattern advances through the manufacturing process. The skeleton is then removed from the lower cylinder using a stripping plate. In particular, the stripping plate of the prior art is positioned adjacent the surface of the lower cylinder, leaving a narrow gap between the stripping plate and the lower cylinder. As the lower cylinder rotates with the skeleton coupled thereon, the leading edge of the stripping plate is oriented to catch the edge of the skeleton and thereby strip the skeleton from the pins as the cylinder continues to rotate.
This prior art stripping device suffers from a number of drawbacks and deficiencies. For instance, the skeleton frequently gets jammed in between the stripping plate and cylinder due to the failure of the stripping plate to effectively remove the skeleton from the all of the pins. At times during the separating process, one or more portions of the skeleton may be curled and positioned relatively close to the lower cylinder as it approaches the stripping plate, such that the stripping plate is not always positioned to catch the leading edges of all of the portions of the skeleton. Therefore, the stripping plate may strip some portions of the skeleton, while other portions remain coupled to the lower cylinder. This non-uniform stripping of the skeleton can cause it to jam between the stripping plate and lower cylinder. Jammed skeletons can cause the manufacturing process to shut down until the problem is corrected. Further, with the prior art devices, when portions of the skeletons remain coupled with the cylinder, multiple skeletons can accumulate on the lower cylinder, eventually reducing the effectiveness of the pin stripping method. Accordingly, such unwanted build-up of skeletons can also force the manufacturing process to be suspended while the waste products are removed. Thus, the use of the prior art stripping plates often results in delays in manufacturing and resultant increases in production costs.
Accordingly, there remains a need for a device that will effectively and completely strip a paper waste product from a two cylinder, one-piece pin assembly without the waste product becoming jammed between the separating cylinder and stripping plate. The present invention fills these needs as well as various other needs.